Anybody re-purposed a beer line chiller as a fermenter glycol chiller?

[Hazelwood Brewery]

I think I would start by recirculating boiling water through the coils to soften and dissolve any syrup or dried beer that had been left in the pipes. I’d probably leave it recirculating for half an hour.

Then I’d fill with the pipes with very hot sodium percarbonate (or cleaner of your choice) and let it sit for half an hour. Rinse through with clean water and catch the outflow. If the outflow contained any particles or was discoloured I’d repeat this step until it drained clean and clear.

When happy it’s all clean, sanitise with star san and flush through with clean water one last time.

 

[hoppyscotty]

have you tested the submersible pump in the water bath? The water in the water bath is maintained at below freezing and is only prevented from freezing by a fan that agitates the water and a recirculation loop, so the water is kept continually moving. So I would have thought that by dropping a submersible pump in there then any water in the pump and in the lines that are in the water would freeze when not in use as the water inside the pump and the part of the line submerged in the water bath would not be agitated but below freezing? Only a thought so happy to be proved wrong.

Personally I was originally planning to put glycol instead of water in the bath and not use the produce lines. Currently have mine set up with a submersible pump in a bucket of glycol, which then pumps the glycol through the product lines and to the FV. The unit has 3 product lines so if/when I get a 4th FV then I will modify but using the product lines in this way seemed the best way to do it. But not using it for serving beer though, just for FV temp control.

 

[peebee]

These shelf coolers (notably the Maxi, but others are probably very similar) have a "crude" thermostat on them. The three I have (two Maxi's and a "clone") had the thermostat set to about 4-5°C so never got close to freezing (all 2nd-hand, but one was factory restored). I did twiddle the Thermostat and did get ice beginning to form near 0°C.

But I bypassed the Thermostat with an Inkbird ITC308 set at 1°C with a 4-5°C deadzone before it triggered the cooling compressor (all ITC308s are defective, so don't think the control can be tightened - however the defect will ensure it is very unlikely the temperature gets above 3 or 4°C set like this).

I do use small submersible pumps to recirc the water bath. The built-in pump is pathetic, but it is a better agitator than the add-in submersible pumps.

 

[ecirpian]

I have had one of these coolers for a few years now but only used it once. I keep meaning to set up in the gazebar and connect to the back of my beer engine, but just haven’t gotten around to it! Anyway, to my question… has anyone used one of these to cool wort after the boil or is it a stupid idea/inefficient? I currently use a hose and water through a coil but don’t like the waste so considering other options.

 

[Hazelwood Brewery]

I have had one of these coolers for a few years now but only used it once. I keep meaning to set up in the gazebar and connect to the back of my beer engine, but just haven’t gotten around to it! Anyway, to my question… has anyone used one of these to cool wort after the boil or is it a stupid idea/inefficient? I currently use a hose and water through a coil but don’t like the waste so considering other options.

I’ve never used my chiller to cool wort but I have on occasion flushed very hot sodium percarbonate through the chiller pipes and that has come out cold. It will use quite a lot of energy to freeze the ice bath so I’m not sure about the energy cost but you’d not use any water for cooling.

I also only flush through a couple of litres so again I’m not able to say if the cooling effect will last through your full kettle volume. You may have to start with a fast flow and gradually slow the flow as the outflow warms.

 

[tigertim]

Thanks for all your help guys. Mine is a Manitowoc Icecore 1 which has an agitator, but doesn't actually have a recirculation pump. I think this is because it's a postmix soft drinks chiller as opposed to a beer line chiller. It does have a soda pump which I could probably repurpose to recirculate, but I'm not sure I need to.

Anyway, I flushed all four coils (it has a still water coil and three product coils) by looping them all together and running near boiling water through, then running PBW through and allowing it to sit, and finally running Starsan through and allowing it to sit. There was zero evidence of anything except crystal clear water or sanitising fluid coming out at any point, so it seems it had been well maintained by its previous owner.

It has a reasonably advanced controller on it - a digital "DFx Series 1e" controller which allows setting of the temperature setpoint and also the hysteresis which is really useful. It also allows setting of operating hours, so that I can only have it operating when I'm likely to be drinking (or fermenting). It's been off all night and the ice bank is still completely intact, so it looks like it really only needs to operate for a short period each day to maintain the ice bank, if there's no real load on it.

I'm very happy with it. Additionally, the ice bank extends nowhere near the area I'd be likely to install the submersible pump, so that's another bonus. I guess I could put some glycol in if necessary, but I worry this would reduce the ability of the machine to generate an appreciable ice bank, which is an important part of how these machines operate.

 

[Druncan]

Hi @tigertim, sounds good. I eventually swapped out the DFX for a STC1000 Elitech STC-1000 Temperature Controller Thermostat Automatic Switch Cooling and Heating, With Temperature Probe Sensor Input, 0.1℃ Resolution as it covers cooling and can power heating directly. Loads of videos show the rebuild. Originally I was using the week timer in our bar as it was perfect. Now my UBC can get my BB 75's FV's down to 1-2*c - I use Acask 30l piped keg jackets for chilling, work really well but cost £100'ish. Have fun!

 

[tigertim]

Oh no - now you've mentioned piped keg jackets, I have a funny feeling that's going to be the next beating my wallet takes!

 

[peebee]

Just to help you (or is that "push you over the edge"?) I started looking into those Acask things: Keg Wrap piped Jacket 20 litre - CPK/KK20P - A-Cask - Pub & Cellar Supplies

They are for 20L and might fit better for Corny kegs?

I don't really need them because I permanently fitted cooling pipes and insulation to my kegs. But that's a major DIY exercise that makes the eye crunching price of those ready-made jackets seem reasonable.

 

[Druncan]

Aye @peebee yes, they work a treat - top birthday pressie, I must have been a good boy

 

[hoppyscotty]

OK finally managed to get myself a chiller and been playing with it tonight. It seems to me the thing runs continually which I would guess supps a fair amount of electricity. I thought about hooking it upto an ink bird so it could kick in and out but then thought the water would freeze once the power cut out as the agitator fan/pump would shut off so I'm back to my original idea of filling with glycol. My thinking here is that I can remove the product lines to create space in the bath, remove the agitator fan/pump, then fill with glycol and control via an Inkbird and maybe even set to a higher temp as even if it was set to a couple of degrees C it would still be cool enough to control a couple or few 30 - 55litre fermenters. Any holes in my plan?

Also anyone recommend any small submersible pumps? was thinking I would use a submersible pump with an Inkbird to control temp for each fermenter and avoid any complicated pump/plumbing and valve arrangement to control multiple fermenters.

Thanks.

 

[aolcot]

I modified my maxi to have the recirculation pump controlled via an inkbird and I've not noticed any issues with freezing and I just use water for cooling.. at the moment its cold crashing a lager and its steady at 1.3 degrees in a cool garage. (or at least that's what the inkbird reckons the temp is).

I've only the one FV but I have been thinking about a 2nd FV more recently and how'd I go about converting the maxi to handle multiple FV's and up'ing the cooling capacity, like glycol.. I think a couple of those FTSs pumps (or similar just as good cheaper option!) put in the bath like you say should work nice...

 

[hoppyscotty]

Thanks. Originally I was going to utilise the product lines for fermentors and tested this on a mates setup. We have a bucket of glycol, a submersible pump in the bucket and lines from the bucket, through the product coil and into the fermenter returning back to the bucket. Works a treat and you can add fermenters upto the number of product coils you have. He has a Grainfather fermenter with the Grainfather cooling kit so all is controlled via the Grainfather.

I was considering the same setup running two Fermzillas with small submersible pumps sat in the bucket each controlled by their own Inkbird so totally independent from eachother.

I guess my concern last night after playing with it was the unit is chugging away all the time so was wanting to shut the unit off when it reached temperature hence wanting to control the actual chiller unit with an Inkbird, but if you have sub-zero water in the bath then shut the whole thing off then I would assume the water in th water bath would freeze, hence my thoughts about using glycol in the actual chiller bath instead of water...then I could delete the stirrer pump and have one less thing whirring around and add an ink bird to the actual chiller unit to shut it off when it reaches its coldest temperature and kick it in again when it warms to a couple of degrees C. Might save a bit of electricity...thats all.

 

[aolcot]

My one doesn't chugg away all the time and the cooler will shut itself down when i guess the bath is at the temp that it wants it to be at and whenever that is, the water hasn't been frozen as i've often had times where the cooler is off, but the recirculation is on pumping water up to the FV... its only when the recirc is on for a while, that the cooler kicks back in.. also during the warmer months, the cooler is on for more naturally.

I'm no expert on these things but I assumed the stirrer/agitator was all part of the recirc pump so I'd only be agitating the water when the recirc was going.. but happy to be told I'm wrong with that respects.. reason I believe that is once the cooler has shut down because the bath is at the right temps and there is no recirc happening, the unit is silent..

Maybe my unit is old and the thermostat doesn't get the water to freezing point anymore lol..

Glycol would solve that though as you say and mitigate freezing risks.. I've never needed to go that far, but if I did convert the maxi to handle multiple FV's using the product lines or somehow put the pumps directly into the bath I'd have to look at Glycol

 

[hoppyscotty]

Interesting, thanks. I had the unit running yesterday evening and whenever I checked on it it was chugging away constantly...I mean the main compressor and chilling unit side of things and not just the stirrer. Maybe I was just unlucky and only ever checked on it at a point where it was on so assumed it wasn't thermostatically controlled. Maybe I'm worrying unnecessarily then.

I was thinking about utilising the recirculation loop but wasn't sure how to actuate the flow to the fermenter without a complex system of actuated valves and how to add fermenters into the system. I was thinking about how I might purpose this for chilling of wort on brewday - maybe recirculate through a coil in a bucket of water and circulate the water through the wort chiller but not sure if the capacity of the chiller could cope with that.

 

[aolcot]

When I turn mine on for a new brew (i do go periods with nothing in the FV so naturally I turn the maxi off), it does take a good few hours for the cooler to get the bath to cooling temps and to turn off finally. Those baths are pretty big lol.. Whenever I fill mine up from empty, I'm looking for leaks after the first few jugs have gone in as I can't believe its still taking more water haha..

Using the recirc is simple if you only have the one FV.. take the top off the maxi, wire a mains plug/flex directly to the recirc pump and then plug that into your firebird.. but yes adding future FV's isn't going to work that well which is where i'm stuck at next.

I have in recent brews just dumped the entire wort into the FV at about 70 degrees and used the cooling of the maxi to bring it down to pitching temps but whilst it does it, I don't think it does it particularly quickly and also, my recent beers have been judged to having dms and i'm pretty sure its caused by that method of cooling. So I'm going to stop doing that and go back to my trusty cooling coil directly in the kettle feed from the mains. I figure that the bath water in the maxi is heating up quite a bit and then having to cool down itself which is never going to be as efficient as cold mains water. I'll collect the warm mains water and use for cleaning/gardening so it won't be wasted as such..

 

[mrhardware]

I usto use a maxi chiller for overclocking a water cooled pc. I seem to remember that there was a small internal temp probe that was in the water bath that allowed you to set a temperature to shut down the chiller when the set temperature was reached.

 

[tigertim]

It's worth remembering these chillers are designed for high, irregular cooling loads (for example, sitting around for hours not doing a huge amount and then chilling continuous pints of beers during half time). For that reason they are actually designed to build up an ice bank in the water bath around the refrigerant coil; when demand is higher than the unit can deliver during these periods, it depletes the ice bank as a cooling reserve, but builds it back up again after the demand has passed.

The agitator generally runs constantly to keep the rest of the bath fluid (in more modern units the controllers can be configured to shut down the agitator our of "opening hours".

So whilst adding glycol will lower the freezing point of the liquid bath, it will also stop the build up of the ice bank unless you set the set point even lower. So the fluid temperature will be lower, but you'll have less cooling capacity without the ice bank.

With my unit, I just use water and often set the controls to cut in at +2C and cut out at 0C so I avoid generating the ice bank and it maintains the bath at just above freezing. As such, I rewired the agitator so that it only runs when the unit is actively cooling.

The truth is, what we use these chillers for is far less than they are designed for so there's generally no real need to have them maintain the water bath at sub-zero temperatures and build up an ice bank. For normal fermentation temperatures of around 10-20C I raise the water bath to around 7-10C because I found that having the water close to zero was causing the temperature of the fermenter to overshoot by a degree or two when cooling. I've only set it close to zero when I've been cold crashing or lagering.

 

[tigertim]

What I meant to add was that it is normal for the units to run for a few hours when first turned on because they are building up the ice bank - they'll then shut off and cycle more infrequently. When set just above freezing with no ice bank, as mine is, it runs for about 15-20 minutes and then sits silent for several hours before running again (unless it has some load on to from a fermenter).

Of course, If you are regularly wanting to bring beers down to pretty much 0C to cold crash or lager, then some glycol probably would be required in the chiller, and a water bath temperature of probably around -4C or so, as long as that is in the design specification of the refrigeration system. I've only ever really crashed to about 4C so that's why I've never worried about glycol.

 

[hoppyscotty]

Interesting on the ice build up. I had a thermometer probe in the bath when I was testing it and it froze so was worried there was something wrong with the unit but sounds normal.

given the capacity of these sounds like my idea of using the continuous circulation loop and an old emmeraion chiller to cool the cooling water might work. Especially if I use it as the wort temp drops to about 45 degrees when the rate of cooling seems to drop off the edge of a cliff.